The data in the videos isn’t great… for one thing, it’s not the behavior I expected (there’s a lot of room for error). Also, it’s just not precise enough data that you could actually do any sort of regression. But I do think that it could be fodder for a conversation about the countable and measurable attributes of prisms and what might make them more and less useful for engineers… and kids could then design the better version of the experiment, with smaller weights, more even distribution of weight, etc.

Also, if you’re curious what the book Facilitating Group Learning is all about, and why I have so many copies, it’s not because I wrote it, it’s just a really good book that any educator or trainer could get a lot from, but is specifically about adult direct education for social justice. Full disclosure: Kaytee works part-time for the organization (Training for Change) founded by the author (George Lakey) and they are distributing copies. That’s why we had ‘em. It was convenient to have identical books, and I thought it was a nice touch to use Facilitating Group Learning to spark some group learning! And I’ve been talking up the book since before they hired Kaytee.

Thanks for shooting this my way, Max. I like the question. I’m curious what you do with student misconceptions. If I’m your student, I might understand the number of books to be related directly to the evenness or oddness of the sides of the polygon. Or I might understand the number of books to be related directly to the number of sides of the polygon. How do you steer me from an incorrect conception to a correct conception. (Bonus point: what is the most effective way to teach this skill to another teacher on the Internet?) Also, I’m curious if this is the sort of question that would work better with digital video or with physical models in the classroom? Thanks!

A coachee of mine used this video in class on Friday — I couldn’t be there to watch or play along, which is pretty sad, but I’ll keep you posted with how it went down with students.

My hope for the video was that it would be a more effective launch into getting students creating physical models than the suggestion in the book (which is basically, close your eyes, imagine what would happen, here’s what should happen, now make a model and test it yourself. Or not).

As for dealing with misconceptions, in the spirit of Teach. Brian. Teach.’s post about Misconceptions, I think my interest in this case would be in students articulating a working hypothesis and coming up with ways to test competing hypotheses. I am not sure if it’s the surface area of the base of the column that increases its strength, or the number of sides. And I’m not sure if there is a good reason that columns even-numbered sides should be stronger in a real-world experiment (easier to get them level? to place the weights perfectly centered?) so I’d be interested in testing that out as well. For this experiment, I’m interested in students reasoning and hypothesis testing skills, in their ability to identify measurable aspects of rectangular prisms, and possibly generating some interest in calculating values for measurable aspects of rectangular prisms.

Possible follow-up video ideas include: holding area of the base constant, holding total surface area constant, holding volume constant. I’d also like to make an ice-melting (or cheese-melting, but I’m cheap) video using the same shapes as the column and holding the same things constant, and seeing whether meltability and column strength are controlled by the same variables.

No joke. And as a solution to the close-your-eyes-and-imagine problem, it’s hard to beat. I like the idea of using it to launch the exploration. Where I think I’d draw the line is in trying to film all your carefully controlled experiments. (For surface area, volume, etc.) I felt that was necessary with the cheese thing only because it’s fairly cumbersome and expensive to melt cheese in the classroom. In the case, the supplies are ubiquitous and it wouldn’t be a bad idea to have students create a list of theories and then test them all one-by-one on their own.

Maybe you create videos on your own because you’re obviously curious about the outcome and to confirm (or dispute) student conclusions if need be, but I hesitate to digitize too much of this obviously cool problem.

You’re right… I was thinking about making the video for the teacher blog-o-sphere because I figured y’all would be interested in the experiments. With the luxury of a classroom of 30 students, I’d have them do the experimentation (and hopefully videotape themselves for their admiring audience of blogging teachers). Thanks for pointing out that question of audience and who does the working/thinking.

For melting ice, I’m thinking that digital video may be the way to go. Both because the problem of making the molds is driving me a little crazy right now, and because ice will take a while to melt. Oh, and lots of schools don’t have the freezer space needed.

Any suggestions on ways to mold ice into various size prisms would be appreciated…